My Fish Setups

Top Left: Betta Tank
Residents:
2 male bettas separated by a divider

Apoc: 3 year old "Red/Black Devil Crowntail"
Red(aka "Old Man"): almost 4 years old "Red Unique Halfmoon"... He's a mutant.

2 Neon Tetras
2 Cardinal Tetras (long story as to why I have 2 of each, was not on purpose)
Live Anubia Plant (I really need more plants *cries*)
Setup:
10 gallon
Heater set at 75-78*F
Internal Whisper Filter
The background is a bamboo place mat.
50% water change every other week
This is a proper betta tank.

Bottom left: Goldfish Tank EDIT: They have been moved to their permanent 30 gallon tank.
Notice how it is not overcrowded. Pretty much every goldfish tank I see on DA has WAY too many fish in it. Goldfish get really big and can live over 10 years when cared for properly. Make sure you remember that when you stock your tank.
Residents:
1 Pearlscale Goldfish (Mochi )
1 Fantail Goldfish (Nori)
Setup:
10 gallon NOTE: They will need a larger (30 gal) tank when they are adults. As they are both still small, a 10 gallon is acceptable.
External Tetra Filter which provides aeration for 2 goldfish. If there were more than 2 then they would defintely need additional aeration.
The background is a bamboo place mat.
50% water change every other week
This is a proper goldfish tank.